# US 8,539,848 B2 · System for evaluating cutting efficiency of root canal rotary instruments > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,539,848 B2 - Document ID: US8539848B2 - Status: Granted - Kind: B2 - Application number: 12/973,833 - Filed: 2010-12-20 - Published: 2011-11-17 - Granted: 2013-09-24 - Earliest claimed: 2010-05-13 - Assignees: National Taiwan University - Applicants: Chow-Shing Shin; Zheng-Cheng Lin; Chun-Pin Lin - Inventors: Chow-Shing Shin; Zheng-Cheng Lin; Chun-Pin Lin - Web page: https://patentgrep.com/patent/US8539848B2 ## CPC - G01M 13/00: Testing of machine parts - A61C 5/42: Files for root canals; Handgrips or guiding means therefor - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - A61C: DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE (non-driven toothbrushes A46B; {tongue scrapers A61B17/24;} preparations for dentistry A61K6/00; preparations for cleaning the teeth or mouth A61K8/00, A61Q11/00) ## Abstract A system for evaluating cutting efficiency of root canal rotary instruments is provided. The system includes a root canal rotary instrument, a driving unit, a cutting object, a prestressing force providing unit and a feeding unit. The root canal rotary instrument is attached on the driving unit, and driven thereby. The cutting object is pressed by the prestressing force providing unit to contact the root canal rotary instrument. The feeding unit feeds the cutting object to the root canal rotary instrument, and the root canal rotary instrument cuts an uncut surface of the cutting object. ## Claims ### Claim 1 A system for evaluating cutting efficiency of root canal rotary instruments, comprising: a root canal rotary instrument; a driving unit, wherein the root canal rotary instrument is attached on the driving unit, and driven thereby; a cutting object; a prestressing force providing unit, wherein the cutting object is pressed by the prestressing force providing unit to contact the root canal rotary instrument; and a feeding unit arranged to feed the cutting object to the root canal rotary instrument, such that the root canal rotary instrument cuts an uncut surface of the cutting object, wherein the driving unit comprises a contra-angle handpiece, the root canal rotary instrument is disposed on the contra-angle handpiece, and the root canal rotary instrument is driven by the contra-angle handpiece, wherein the driving unit further comprises a first sliding member, the contra-angle handpiece is disposed on the first sliding member, the first sliding member slides in a first direction and a second direction to modify a position of the root canal rotary instrument, and the first direction is perpendicular to the second direction, wherein the cutting object comprises a first cylinder, and the feeding unit rotates the first cylinder. ### Claim 2 (depends on 1) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 1, arranged such that the root canal rotary instrument cuts a first periphery surface of the first cylinder, the feeding unit rotates the first cylinder, and the root canal rotary instrument continuously cuts the uncut portion of the first periphery surface. ### Claim 3 (depends on 2) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 2, wherein the cutting object comprises a second cylinder, the feeding unit rotates the second cylinder, and the root canal rotary instrument is located between the first cylinder and the second cylinder, arranged such that the root canal rotary instrument cuts a second periphery surface of the second cylinder, the feeding unit rotates the second cylinder, and the root canal rotary instrument continuously cuts the uncut portion of the second periphery surface. ### Claim 4 (depends on 3) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 3, wherein the first cylinder and the second cylinder are rotated respectively in opposite directions. ### Claim 5 (depends on 4) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 4, wherein the first cylinder and the second cylinder are rotated with a speed of 1/40˜1/50 rounds. ### Claim 6 (depends on 3) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 3, wherein the prestressing force providing unit further comprises a second sliding member, the second cylinder is disposed on the second sliding member, the second sliding member slides in the first direction, and the second sliding member pushes the second cylinder contacting the root canal rotary instrument. ### Claim 7 (depends on 6) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 6, wherein the second sliding member comprises an elastic element, and the elastic element pushes the second cylinder contacting the root canal rotary instrument. ### Claim 8 (depends on 7) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 7, wherein the elastic element is spring, the elastic element provides a prestressing force toward the second cylinder, and the prestressing force is between 5N˜10N. ### Claim 9 (depends on 1) A method for evaluating cutting efficiency of root canal rotary instruments, comprising: providing the system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 1; rotating the root canal rotary instrument; feeding the cutting object by the feeding unit toward the root canal rotary instrument to be cut thereby; and evaluating cutting efficiency of the root canal rotary instrument by measuring weight variation of the cutting object. ### Claim 10 (depends on 9) The method for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 9, further comprising modifying a position of the root canal rotary instrument in a second direction to change contact position of the root canal rotary instrument on the cutting object. ### Claim 11 (depends on 1) The system for evaluating cutting efficiency of root canal rotary instruments as claimed in claim 1, wherein the cutting object is made of acrylic.